In the field of medical infusion devices including so-called “syringe pumps” and “ambulatory infusion pumps”, typically a pre-filled medication syringe or reservoir is mechanically driven or controlled by a microprocessor to deliver a prescribed amount or dose of a drug or fluid at a controlled rate to a patient through an infusion line fluidly connected to the syringe or reservoir. Drugs or fluids delivered to a patient by way of syringe pumps and ambulatory infusion pumps can include, but are not limited to: therapeutic agents; nutrients; drugs; medicaments such as antibiotics, blood clotting agents, and analgesics; and other fluids. The devices can be used to introduce the drugs or fluids into patients' bodies utilizing any of several routes such as, for example, intravenously, subcutaneously, arterially, or epidurally.
Examples of syringe pumps and related components are disclosed in U.S. Pat. No. 4,978,335 titled “Infusion Pump with Bar Code Input to Computer,” U.S. Pat. No. 8,182,461 titled “Syringe Pump Rapid Occlusion Detection System,” and U.S. Pat. No. 8,209,060 titled “Updating Syringe Profiles for a Syringe Pump.” As used throughout this disclosure, the term “syringe pump” is intended to generally pertain to any device which acts on a syringe to controllably force fluid outwardly therefrom. Examples of ambulatory infusion pumps and related components are disclosed in U.S. Pat. No. 7,654,976 titled “Drug Pump Systems and Methods,” U.S. Pat. No. 8,030,891 titled “Ambulatory Medical Device with Electrical Isolation from Connected Peripheral Device,” U.S. Pat. No. 7,967,773 titled “Two Piece Medication Cassette Closure Apparatus and Method,” U.S. Pat. Applic. Pub. No. 2011/0133946 titled “Guided User Help System for an Ambulatory Infusion device,” and U.S. Pat. Applic. Pub. No. 2011/0137239 titled “Advanced Step Therapy Delivery for an Ambulatory Infusion Pump and system.” As used throughout this disclosure, the term “ambulatory infusion pump” is intended to generally pertain to any device which acts on a reservoir to controllably force fluid outwardly therefrom, or otherwise regulate a flow of fluid to a patient.
In use of medical infusion devices such as syringe pumps and ambulatory infusion pumps, it may be desirable or even necessary in particular circumstances to provide means for limited direct control of the devices by the patients themselves. Such functionality may be desirable when, for example, a patient is receiving a medication to alleviate pain and an attending physician or practitioner has deemed it permissible for the patient to control, within limits, how frequently the pain medication is administered and how much is delivered from the infusion device. However, infusion devices often have operational complexities that exceed the training or experience of typical patients; and controlled substances such as pain medications often have strict “hard” volume and frequency administration limits for overdose prevention and patient safety. Thus it is often desirable to employ an accessory known as a “remote dose cord” with an infusion device, for such “self-administration” of pain medication by and to the patient. A remote dose cord typically includes a hand-held controller, and an electrically-conductive, insulated electrical transmission cord or cable extending from the controller which terminates in an electrical connector that is configured for coupling to an electrical connection port of the infusion device. Remote dose cords usually are, by design, relatively easy to operate: the hand-held controllers typically have only one clearly marked button for the patient to push, and are ergonomically designed to accommodate use by patients having limited dexterity, motion, strength, or lack of visual acuity. Remote dose cords typically also indicate when a next dose is “available” or “unavailable” to the patient through use of a lighted or blinking light-emitting diode (LED), or other signaling means such as an audible beeper or a vibrating hand-held controller, or any combination of such signaling means, in cooperation with software with or for medical infusion devices.
The electrical connector, at the end of the remote dose cord opposite the hand-held controller, typically has a plurality of pins which engage corresponding sockets in an electrical connection port of the infusion device. The pins in the connector, when engaged in the sockets in the electrical connection port of the infusion device, provide electrical power and signal transfer capabilities between the remote dose cord and the infusion device. Accordingly when, for example, a patient pushes the button on the hand-held controller of the remote dose cord to receive a desired bolus of pain medication, a command signal responsively generated by circuitry within the controller is transmitted through the cord and connector and into the infusion device. The command signal is then processed by the infusion device for a determination of whether, for example, it is safe to deliver the requested pain medication to the patient.
Unfortunately, problems may arise in use of known electrical connectors that couple the remote dose cords to the infusion devices. Known electrical connectors may be subject to external forces that may compromise their structural integrity when the pins are engaged in the sockets of the infusion device. For example, a patient may mishandle a connector by trying to twist or rotate it while it is coupled to an electrical connection port in an infusion device; or the pins in the connector may be subject to a rotating or other deleterious force or load when, for example, the connector is inadvertently bumped or momentarily comes into contact with a stationary object such as a wall while the patient is walking with the device. Regardless of a particular instance of mishandling or external force, such electrical connectors and the cords from which they extend are intended to remain stationary and not twist with respect to the infusion device. Thus, such twisting motions or rotating forces can result in broken pins and other failures in remote dose cords and infusion devices.
It would therefore be useful and advantageous to provide rotatable electrical connectors with remote dose cords, which would not be adversely affected by twisting or rotating forces while coupled to electrical connection ports in infusion devices.